From EP 2150165 B1 it is known to configure an impeller pump of this kind in highly integrated design for use in a dishwasher. Here an annular pump chamber of circular cylindrical shape, which surrounds an inlet into the pump chamber and an impeller disposed in the pump chamber, is provided, wherein an external wall of the pump chamber is formed by a heating device. At that end of the pump chamber which is remote from the impeller, or on an upper rim or cover of the pump casing, there is provided an outlet from the pump chamber, from which the heated and conveyed medium is discharged.